I have a question about whether this is a bug or not. While on the hoverboard and pressing shift, if I suddenly turn around and shoot heat seeking rockets, they'll fly backwards. Also, if I do the same up and down, they'll fly backwards down? Is this a bug? I'll get a screenie in a second.

This is a feature present in the physics of JJ2. It is similar to how the weapon shoots faster if you shoot while running. Also, you don't have to be on a hoverboard, or be using seekers. Basically, the projectile shoots out at the instantaneous velocity of your character when you are shooting it.

++Wheel of Time

I noticed that. Anyone can cause the glitch, it's nothing serious.